JPS60238490A - Rust preventinve - Google Patents

Abstract

PURPOSE:To obtain the titled aq. rust preventive having excellent characteristics by incorporating an aq. synthetic resin into an aq. disperse liquid of the amine salt of aliphatic carboxylic acid or oxycarboxylic acid and the alkaline earh metal salt of higher aliphatic carboxylic acid and oxidized wax. CONSTITUTION:The rust preventive is obtained by blending 5-20pts.wt. of >=1 kind of salt selected from a morpholine derivative contg. aliphatic coarboxylic acid or aliphatic oxycarboxylic acid and a tertiary base and a heterocyclic compd. selected from a group consisting of pyridine and its derivative, 5- 20pts.wt. of >=1 kind selected from a group consisting of alkaline earth metal salts of higher aliphatic carboxylic acid, petroleum sulfonic acids, and oxidized wax, 3-15pts.wt. of one kind of carboxylic acid selected from oxidized wax and higher aliphatic acid, 95-98.5pts.wt. of an aq. disperse liquid, and further 5-1.5pts.wt. of aq. synthetic resin. An aq. rust preventive capable of forming a coated film having excellent gloss, hardness, drying property, and adhesiveness and having a highly rust preventive property can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a rust preventive agent, particularly to a rust preventive agent suitable for rust preventing a portion of an automobile chassis and various parts of the chassis portion.

(Prior Art) Many metal rust inhibitors have been proposed and used to prevent corrosion or rusting of metals. Among these, chassis black (black resin paint) is currently commonly used as a chassis rust preventive agent for automobiles. However, Chassis Black was not fully satisfied in terms of rust prevention performance (1), and improvements were required.
Since it is necessary to dry and cure with hot air at a high temperature such as 30 minutes at ℃, there are problems such as consumption of thermal energy.

As an alternative to this, there is a solvent-based wax rust preventive agent that has excellent rust preventive properties and can be dried at room temperature. This solvent-based wax rust preventive agent has a wide range of choices regarding its constituent components, and various products that are practically usable are now in widespread use. However, due to the risk of fire outbreak, there are restrictions on where they can be handled and in quantity.
In addition to problems such as deterioration of the working environment due to organic bath agent vapor during work, one solution to this problem is to save resources.
Currently, there is a long-awaited demand for water-based rust inhibitors.

However, there is no doubt that water is one of the factors that cause rust on metals.There is no doubt that water is one of the factors that cause rust in metals.For water-based wax rust preventive agents, the composition of the ingredients is of course important, but the drying behavior on the applied surface and the minute shape of the dried coating film are important. There are many problems compared to solvent-based products such as
As a result, it is generally said that they are inferior to solvent-based products in the important rust prevention performance. Therefore, studies have been conducted to find a water-based rust preventive agent that can overcome these drawbacks and have performance comparable to that of solvent-based rust preventive agents, and a water-based wax rust preventive agent has been proposed in Japanese Patent Application Laid-open No. 138472/1983. Many wax rust preventives, whether solvent-based or water-based, are so-called homogeneous dissolution systems.
It is a dispersion type containing wax fine particles, and is generally used in a relatively thick film, or strictly speaking, the dry coating film tends to contain a continuous phase even if there is no visible difference to the naked eye.In particular, water-based wax rust preventives Therefore, for this purpose, it is important to select a combination of a wax rust preventive component that has a thick film retention ability and an auxiliary rust preventive component that forms and obtains a continuous phase as much as possible. . By the way, the water-based wax rust preventive agent described in JP-A No. 56-188472 is used for rust prevention of the above-mentioned parts of the automobile chassis and the undercarriage of the automobile by simply adding a black color and a coloring agent; However, since water-based wax rust preventive agents are waxy in nature, the coating film itself is relatively soft, sticky, and lacks gloss. Particularly in the lower part of automobiles, there is a lot of chipping caused by stones, earth and sand, and adsorption of dust, etc., and there is a current demand for rust preventive agents that can resist chipping and form a paint film that is free of stickiness. be.

(Disclosure of the Invention) As a result of various studies in order to solve one problem of such water-based wax rust inhibitors, the present inventors have developed a morpholine derivative having an aliphatic carboxylic acid or aliphatic oxycarboxylic acid 88th base as component a. , 5 to 20 parts by weight of at least one salt with a heterocyclic compound selected from the group consisting of pyridine and pyridine derivatives, and alkaline earth metal salts of higher aliphatic carboxylic acids, petroleum sulfonic acids, and oxidized waxes as component b. An aqueous dispersion of 95 to 98.5 parts by weight of 5 to 20 parts by weight of one or more selected from the group consisting of 8 to 15 parts by weight of one or more carboxylic acids selected from oxidized wax and higher fatty acids as component C.
By adding 6 to 1.5 parts by weight of a water-based synthetic resin to the weight part, the physical properties of the paint film that cannot be obtained with conventional water-based emulsion rust preventives are improved, such as gloss, hardness, drying properties, and adhesion of the paint film. The inventors of the present invention have found that a rust preventive agent with improved corrosion resistance, etc., and which can be coated in a thick film with high safety and has high rust preventive properties has been achieved, and the present invention has been achieved.

The (a+ acid component aliphatic oxycarboxylic acids of the present invention include δ-oxyvaleric acid, δ-oxycaproic acid, and γ-
Examples include oxybutyric acid, γ-oxyvaleric acid, γ-oxystearic acid, etc. Higher aliphatic carboxylic acids used in component a) of the dispersion used in the present invention include saturated and unsaturated monocarboxylic acids,
Saturated and unsaturated polycarboxylic acids, fatty acids from natural fats and oils that are mixtures thereof, polymers of unsaturated fatty acids, and the like can be mentioned. □More specifically, saturated monocarboxylic acids such as capric acid, lauric acid, myristic acid, valmitic acid, stearic acid, etc., and unsaturated monocarboxylic acids such as undecylenic acid, oleic acid, elaidic acid, cetoleic acid, etc. Examples of polycarboxylic acids include adipic acid, speric acid, cepatic acid, etc.
As the unsaturated polycarboxylic acid, linoleic acid, eriostearic acid, lylunic acid, etc. can be used. In addition, fatty acids derived from natural oils include vegetable oil fatty acids such as linseed oil, castor oil, and coconut oil, animal oil fatty acids such as beef tallow, wool fat, and pine kola oil, and polymers of unsaturated fatty acids such as dimer acid. Other dimer acid, oleic acid,
A maleated product of castor oil fatty acid can be used. Of these, it is particularly preferable to use a saturated carboxylic acid having an amount of 0□2 to 018.

In particular, in the case of oxycarboxylic acids, they are stable as their alkali salts or tertiary amine salts, but in the free state they form lactones or lactides and are inactivated. Of course, it has the property of becoming polyester through intermolecular polymerization even when left alone. For this reason, it plays the role of a water-soluble emulsifier (surfactant) as a tertiary amine salt of oxycarboxylic acid before use (rust preventive stage), and after the coating film is formed after use (after application), it acts as a water-soluble emulsifier (surfactant). With the volatilization of the grade amine, free hydroxycarboxylic acid teractone or lactide is formed, and a polyester film is formed, thereby significantly enhancing the physical properties of the entire coating film.

As the alkaline earth metal scrap salt of higher aliphatic carboxylic acid, which is the next component), any of the above-mentioned calcium salts, barium salts, and magnesium salts of higher aliphatic carboxylic acids can be effectively used. It is well known that calcium salts are common as alkaline earth metals in petroleum sulfonates and are often used in solvent-based rust preventive agents.Also, alkaline earth metal salts in oxidized waxes can be obtained from petroleum. Calcium salts and barium salts of oxidized wax obtained by oxidizing paraffin wax are effective.

Although each of these has poor antirust ability on its own, they have a synergistic effect with the wax component, that is, they are effective in forming a continuous phase in the coating film, improving the thixotropic properties of the product, and are effective in preventing the sagging of the coating film.

The oxidized wax of component (C) is the aforementioned petroleum wax, and the higher fatty acids include common higher aliphatic carboxylic acids and fatty acids from natural oils.These wax components have a synergistic effect on coating. Effective for film retention and rust prevention performance - The dispersion used in the present invention is the above (a)
, (b), and (c) components are dispersed in water, but components (in this report) and (C) are well known as active ingredients of oil-based rust preventives, and all of them are water-insoluble or poorly soluble. However, when used in an aqueous system, it is necessary to emulsify or solubilize using a surfactant.For this purpose, it is necessary to use surfactants such as aliphatic polyglycol esters and aliphatic alkanolamides. Emulsification can be made solubilized using aliphatic polyoxyethylene esters, aliphatic alcohol polyoxyethylene ethers, polyethylene glyco-rusorbitan fatty acid esters, alkaline earth metal salts of fatty acids, etc. Even in cases b) and c), the inherent anti-corrosion properties of the ingredients are significantly reduced, resulting in a lack of practicality.

On the other hand, the amine salt of aliphatic carboxylic acid or aliphatic oxycarboxylic acid as component a is more effective for the purpose of rust prevention than the above-mentioned surfactants, and component a itself forms a polyester film after forming the coating film. and strengthens the entire coating film.

Next, (a) constituting the aqueous dispersion in the present invention,
The blending amounts of components (b) and (0) are as follows:
The reason for this is that the characteristics of each component are adjusted to maintain the anti-rust performance, which is the main purpose of the dispersion. Various methods can be considered for dispersing this blending system in an aqueous system in which it is important to wash and disperse the blended system, but there are no particular limitations in this case.

If the amount of the active ingredient in the aqueous dispersion system is less than the specified amount, the viscosity of the product will decrease, resulting in a loss of paint film retention, and the paint film will deteriorate due to sagging, etc.

°Rust prevention effect is lost. In this case, there is a method to adjust the viscosity to the required level by adding a thickener separately, but this is not preferable in terms of rust prevention performance. In addition, there is a problem that the remaining coating film after water evaporates during the second coating operation is so thin that effective antirust performance cannot be obtained. On the other hand, when the amount of active ingredients (a) to (0) exceeds the specified amount,
- It is expected that the remaining coating film after water evaporation will be obtained as a thick film in the second application process, but the viscosity of the product itself will increase dramatically, it will tend to gel, and the emulsion will lack stability. There are major problems with workability when using it, and it lacks practicality.

Next, the actual blending ratio of the components (al, (b) and (0)) may vary within the above range;
Originally, each component alone has poor rust prevention effect, but the synergistic effect of their combination maintains excellent rust prevention performance □. That is, to obtain better effects, (0) component I
By blending the medium component at a ratio of 1.2 to 4 parts by weight with respect to the amount of M, an excellent continuous phase is formed, which is particularly effective in improving rust prevention.

- The balance of the blending system of components (a) to (C) is 611M
If not, the rust prevention performance will be significantly reduced and excellent effects will not be obtained. In addition, the (a) component is the Φ) component and (0
) is an important component for making the component water-based, and (b).

For 1 part by weight of component (C) (al content: 0.5 to 1).

A more stable emulsion can be obtained by blending at a ratio of 5 parts by weight. Therefore, if the amount of component (a) is too small, the emulsified state will become unstable, a good emulsion will not be obtained, and rust prevention will occur. There will be no effect.

Moreover, if the amount of component (a) exceeds the specified amount, the ability to form a coating decreases, causing a decrease in rust prevention ability, which is not desirable.

Under such conditions, the active ingredients (a), (b), (c
When dispersed in an aqueous system, it is most preferable to disperse the active ingredient in a total of 20 to 35 parts by weight in the entire formulation system.

The rust preventive agent of the present invention is a dispersion of components (a), (b), and (c) dispersed in water and mixed with a water-based synthetic resin. Examples of the water-based synthetic resin include acrylic, alkyd, and epoxy. There are various types such as vinyl acetate type and vinyl acetate type, but acrylic type is preferable due to its compatibility with waxy materials, drying properties, glossiness, etc. Coloring agents that may be added as necessary include carbon black, which is commonly used as a black coloring agent, as well as iron oxide pigments and dyes. As the black coloring agent, carbon black is preferable. In the present invention, when a coloring agent is used, 5 to 10 parts by weight of a coloring agent such as carbon black is blended in advance to 95 to 90 parts by weight of the aqueous synthetic resin emulsion, A colored aqueous synthetic resin is blended into the above-mentioned dispersion. Although various mixing ratios can be considered, 95 to 98.5 parts by weight of the dispersion and 5 to 1.5 parts by weight of the aqueous synthetic resin containing a coloring agent as required are blended. The reason for this is that when the amount of water-based synthetic resin is increased by 5 parts by weight, it is effective for improving gloss, coating hardness, etc., but as the resin content increases, rust prevention becomes significantly worse. On the other hand, the tendency of coating films to crack and to have poor adhesion is detrimental to their stability. On the other hand, when the amount of the water-based synthetic resin component is less than 1.5 parts by weight, it is effective with little effect on rust prevention, but it lacks gloss and coating hardness, resulting in poor durability. This is because there are problems such as waxy stickiness remaining on the paint film.

The rust preventive agent of the present invention having such a structure not only has excellent rust prevention properties, but also provides a glossy, non-sticky, and relatively hard coating film when dried under constant flooding71. Compared to the black resin paints (oil-based and water-based Sharn Black) that are commonly used as Charnow rust preventive agents, it has the advantages of significantly improved rust prevention, reduced work costs, and resource savings. Since the waxy rust preventive agent has excellent coating film retention, which is a material property, it can fully meet the requirements of JM film. In addition, since water is used as a medium and no organic solvent is used, there is no danger of fire, and the working environment is highly safe, making it extremely useful industrially. When applying the coating to automobiles, it is also possible to apply the coating to so-called suspension parts such as suspension wheels, transverse links, rear wheels, gasoline tanks, strut springs, etc. in advance and assemble the parts before assembly. May be applied after assembly as 0
Of course, you may apply a rust preventive agent made by Futomei instead of using the conventional method. In this case, if a conventional black coating is applied underneath, it is not necessary to add the 7n coloring agent to the rust preventive of the present invention.

In addition, when applying the rust preventive agent of the present invention to a member such as a suspension member, it must be handled in a box immediately after application, but in such a case, the temperature at 60°C
You just need to dry it for about 80 minutes at a temperature lower than the baking temperature of normal paint.

(Examples of the Invention) Next, the present invention will be explained with reference to Examples and Comparative Examples.0 Examples 1 to 7. Comparative Examples 1 to 5 The ingredients shown in Table 1 below were blended (parts by weight) Example 1
~? The nonvolatile content, rust prevention properties, dryness to touch, dispersion state, and surface hardness of each of the rust preventive compositions of Comparative Examples 1 to 5 were evaluated, and the results are also listed in Table 1. The test method and evaluation are as follows.

(1) Rust prevention test 5 as a dry coating □ on a polished steel plate with a clean surface
Spray the sample to obtain 0 ± 5 microns, 24
After being allowed to dry for a period of time, a salt spray test was conducted according to the method specified in JIS 22871, and the time required for rust to begin to form was indicated.

(2) Dry-to-touch A test piece sprayed with a sample to a coating film thickness of 50±5 microns is left in a room at 20°C, and the dry-to-touch time is measured in a conventional manner.

(+31 dispersion state By visual inspection, (4) Surface hardness Pencil hardness.

(Effect of the invention) As described above, the rust preventives of the present invention (Examples 1 to 7) are all in a stable dispersion state, and by blending the aqueous synthetic resin into the specific dispersion liquid, the drying time can be improved. The time is significantly shortened, and the coating film surface hardening effect is improved without impairing the rust prevention effect.
It maintains excellent rust prevention performance, and has the ability to be used for the purpose of rust prevention for automobile chassis parts and undercarriages.

Continuation of page 1 @ Inventor How many parts Enemy side Atsugi I Sen 0 Inventor Takayanagi overwhelming victory Tokyo 1 560-2 Okazu Koku 2 Nissan Motor Co., Ltd. Technical 2-

Claims (1)

[Scope of Claims] L a) A small amount of a salt of an aliphatic carboxylic acid or an aliphatic oxycarboxylic acid and a heterocyclic compound selected from the group consisting of morpholine conductors, pyridine, and pyridine derivatives having an 8th class base. 5 to 20 parts by weight of one kind, b)
5 to 20 parts by weight of one or more selected from the group consisting of higher aliphatic carboxylic acids, petroleum sulfonic acids, and alkaline earth metal salts of oxidized waxes, and one selected from the group consisting of oxidized waxes and higher aliphatic waxes. A rust preventive agent comprising 5 parts by weight of an aqueous dispersion of 8 to 15 parts by weight of a seed carboxylic acid dispersed in water and 5 to 1.5 parts of an aqueous synthetic resin.